There is a continuing need for polymeric materials with physical characteristics that exceed the properties of traditional systems. The search for such improvements in the 1950's led to the incorporation of bulky aromatic groups into polymer back-bones and thereby reducing chain motion which in turn resulted in significant improvements in strength and thermal stability relative to aliphatic systems. (See The Development of Plastics, Editors S. T. I. Mossman and P. J. T Morris, Royal Soc. Chem. 1994, Cambridge.) More recent advancements in the 1970's through 1980's focused on the incorporation of inorganic fillers into polymers via blending to impart some of the desirable physical characteristics of the inorganic filler to the polymer. This effort has included the blending of micron-sized particulates to particulates that are nanoscopic in one-dimension. All of these have attained only incremental improvements in physical properties. (See George Wypnch, Fillers, Chem Tec Publishing Ontario, Canada, 1993; B. K. G. Theng, Developments in Soil Science, Vol 9: Formation and Properties of Clay-Polymer Complexes, 1979; E. P. Giannelis, R. Krishnamoorti, and E. Manias, Adv. Polym. Sci., 138, 107, 1999.) Nanocomposite polymers formed by the incorporation of reinforcements that are truly nanoscopic in all three dimensions and which are capable of complete molecular level dispersion have also been reported.
Polyhedral oligomeric silsesquioxane (“POSS”) dimers, cage molecules, polymers and resins as well as polyhedral oligomeric silicate (“POS”) (spherosilicate) cage molecules, polymers and resins are increasingly being utilized as building blocks for the preparation of performance polymeric materials. Their nanometer size and unique hybrid (inorganic-organic) chemical composition are responsible for the many desirable property enhancements that have been observed upon incorporation of POSS/POS reagents into polymer systems. For example, U.S. Pat. No. 5,858,544 to Holl et. al. discloses methods of using nanoscopic POSS building blocks to modify the surfaces of metals to improve their corrosion resistance. Similarly, U.S. Pat. Nos. 5,412,053 and 5,484,867 to Lichtenhan et. al., the contents of which are incorporated herein by reference, and U.S. Pat. No. 6,252,030 to Zank et. al., discuss the polymerization of POS/POSS entities. The prior art, however, does not afford the nanoscale reinforcement of polymer chains or of polymer morphologies via the method of reactive grafting POS/POSS entities directly onto polymers, nor does the prior art describe the use of grafted POS/POSS and their corresponding copolymers as compatibilizing agents for non-grafted or nongraftable POSS entities. In addition, there is a need for a method to incorporate POS/POSS segments into polymers for the purposes of reducing interfacial tensions to control polymer microstructure, nanostructure and interfacial compatibility.